Leukotriene B4 receptor levels and intracellular calcium signalling in polymorphonuclear leukocytes from patients with Crohn's disease
Research output: Contribution to journal › Journal article › Research › peer-review
Standard
Leukotriene B4 receptor levels and intracellular calcium signalling in polymorphonuclear leukocytes from patients with Crohn's disease. / Bouchelouche, P N; Berild, D; Nielsen, O H; Elmgreen, J; Poulsen, H S.
In: European journal of gastroenterology & hepatology, Vol. 7, No. 4, 04.1995, p. 349-56.Research output: Contribution to journal › Journal article › Research › peer-review
Harvard
APA
Vancouver
Author
Bibtex
}
RIS
TY - JOUR
T1 - Leukotriene B4 receptor levels and intracellular calcium signalling in polymorphonuclear leukocytes from patients with Crohn's disease
AU - Bouchelouche, P N
AU - Berild, D
AU - Nielsen, O H
AU - Elmgreen, J
AU - Poulsen, H S
PY - 1995/4
Y1 - 1995/4
N2 - OBJECTIVE: To investigate the leukotriene B4 (LTB4) signal transducing mechanism in polymorphonuclear neutrophils (PMNs) from patients with Crohn's disease.METHODS: Cytosolic free calcium ([Ca2+]i), inositol (1,4,5)-trisphosphate [(1,4,5)-IP3] chemotaxis, LTB4 receptor number and affinity were investigated in peripheral PMNs from 11 patients with Crohn's disease and 11 healthy controls.RESULTS: There was a slight reduction (P = 0.31) in the number of LTB4 receptor sites per cell expressed on PMNs (mean Bmax 931) from nine of the 11 patients studied compared with the healthy controls (mean Bmax 1095). LTB4-mediated (1,4,5)-IP3 formation and the increase in [Ca2+]i were markedly decreased in PMNs from the 11 patients with Crohn's disease [(1,4,5)-IP3, mean +/- SEM 12 +/- 0.84 and 27.4 +/- 1.4 pmol/l/tube for patients and controls, respectively; [Ca2+]i, mean +/- SEM 295 +/- 2.75 and 598 +/- 4.7 nmol/l for patients and controls, respectively]. The decrease in calcium might be related to the decrease in Bmax (P < 0.05). Ionomycin, a calcium ionophore which bypasses the initial steps of LTB4 receptor activation, showed only a minor difference in peak [Ca2+]i between PMNs from patients and controls. LTB4-directed chemotaxis showed that the sensitivity to suboptimal concentrations of LTB4 (1.0 nmol/l) was significantly depressed in PMNs from patients (P < 0.05).CONCLUSION: Peripheral PMNs from patients with Crohn's disease had a small deficit in the expression of LTB4 receptors. This deficiency was paralleled by marked alterations in cellular signalling. Whether these results are specific to Crohn's disease or simply result from the exposure of circulating PMNs to elevated levels of LTB4 remains to be established.
AB - OBJECTIVE: To investigate the leukotriene B4 (LTB4) signal transducing mechanism in polymorphonuclear neutrophils (PMNs) from patients with Crohn's disease.METHODS: Cytosolic free calcium ([Ca2+]i), inositol (1,4,5)-trisphosphate [(1,4,5)-IP3] chemotaxis, LTB4 receptor number and affinity were investigated in peripheral PMNs from 11 patients with Crohn's disease and 11 healthy controls.RESULTS: There was a slight reduction (P = 0.31) in the number of LTB4 receptor sites per cell expressed on PMNs (mean Bmax 931) from nine of the 11 patients studied compared with the healthy controls (mean Bmax 1095). LTB4-mediated (1,4,5)-IP3 formation and the increase in [Ca2+]i were markedly decreased in PMNs from the 11 patients with Crohn's disease [(1,4,5)-IP3, mean +/- SEM 12 +/- 0.84 and 27.4 +/- 1.4 pmol/l/tube for patients and controls, respectively; [Ca2+]i, mean +/- SEM 295 +/- 2.75 and 598 +/- 4.7 nmol/l for patients and controls, respectively]. The decrease in calcium might be related to the decrease in Bmax (P < 0.05). Ionomycin, a calcium ionophore which bypasses the initial steps of LTB4 receptor activation, showed only a minor difference in peak [Ca2+]i between PMNs from patients and controls. LTB4-directed chemotaxis showed that the sensitivity to suboptimal concentrations of LTB4 (1.0 nmol/l) was significantly depressed in PMNs from patients (P < 0.05).CONCLUSION: Peripheral PMNs from patients with Crohn's disease had a small deficit in the expression of LTB4 receptors. This deficiency was paralleled by marked alterations in cellular signalling. Whether these results are specific to Crohn's disease or simply result from the exposure of circulating PMNs to elevated levels of LTB4 remains to be established.
KW - Adult
KW - Calcium/analysis
KW - Chemotaxis
KW - Crohn Disease/physiopathology
KW - Cytosol/chemistry
KW - Female
KW - Humans
KW - Inositol 1,4,5-Trisphosphate/metabolism
KW - Leukotriene B4/physiology
KW - Male
KW - Middle Aged
KW - Neutrophils/chemistry
KW - Receptors, Leukotriene B4/analysis
KW - Signal Transduction
M3 - Journal article
C2 - 7600141
VL - 7
SP - 349
EP - 356
JO - European Journal of Gastroenterology and Hepatology, Supplement
JF - European Journal of Gastroenterology and Hepatology, Supplement
SN - 0954-691X
IS - 4
ER -
ID: 218727157